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A222816
Numbers k that divide the base-5 reversal of k.
2
8, 48, 144, 208, 248, 744, 1008, 1248, 3744, 5008, 5208, 6048, 6248, 18744, 25008, 26208, 30048, 31248, 90144, 93744, 125008, 126008, 130208, 131208, 150048, 151048, 155248, 156248, 450144, 468744, 625008, 631008, 650208, 656208, 750048, 756048, 775248, 781248
OFFSET
1,1
COMMENTS
The base-B reversal of k is obtained by writing k in base B and reversing the order of the digits.
LINKS
Leonard F. Klosinski and Dennis C. Smolarski, On the Reversing of Digits, Math. Mag., 42 (1969), 208-210. [Gives a(1)]
N. J. A. Sloane, 2178 And All That, arXiv:1307.0453 [math.NT], 2013; Fib. Quart., 52 (2014), 99-120.
EXAMPLE
8 in base 5 is 13_5; its reverse is 31_5, which is 16 in base 10, and 8 divides 16, so 8 is in the sequence.
MATHEMATICA
Select[Range[10^6], Divisible[s=FromDigits[Reverse@IntegerDigits[#, 5], 5], #]&&s!=#&] (* Giorgos Kalogeropoulos, Aug 20 2021 *)
PROG
(PARI) isok(n) = (rdn = subst(Polrev(digits(n, 5)), x, 5)) && (rdn != n) && (rdn % n) == 0; \\ Michel Marcus, Oct 10 2014
CROSSREFS
Sequence in context: A121355 A227499 A168012 * A280056 A035471 A209443
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Mar 13 2013
EXTENSIONS
More terms from Alois P. Heinz, Mar 13 2013
STATUS
approved